How Is Melanoma Different From Other Skin Cancers?

Melanoma forms in the outer layer of the skin and affects melanocytes. Unlike many other types of skin cancer, melanoma can grow quickly. If it isn’t detected early, cancer cells can spread to lymph nodes and other parts of the body, making treatment more challenging.

Melanoma can appear in several forms, and each subtype may look a little different.

Types of Melanoma

The most common form is cutaneous melanoma, which develops on the skin. There are four main subtypes of cutaneous melanoma:

• Superficial spreading melanoma
• The most common type
• Often appears as a changing mole
• May have asymmetry, irregular borders, uneven color or grow larger over time
•  Nodular melanoma
• Often appears as a raised bump
• May be black, brown, red, pink or flesh-colored
• Tends to grow more quickly than other types
  
• Lentigo maligna melanoma
• Often appears as a flat, dark patch that resembles an age spot
• Most commonly develops in older adults on skin that has received many years of sun exposure
  
• Acral lentiginous melanoma
• Develops on areas not typically exposed to the sun, such as the palms of the hands, soles of the feet or under the nails
• Not typically linked to sun exposure
• Can be harder to recognize and may be diagnosed later

Other less common types of melanoma

Less commonly, melanoma can develop in other parts of your body, including:

• Ocular melanoma, which affects the eye
• Mucosal melanoma, which develops in a mucous membrane, such as inside the nose, mouth, anus or vagina

What Are the Most Common Warning Signs?

Melanoma often appears as a new spot or a change in an existing mole. Paying attention to changes in your skin is one of the most important ways to detect it early.

Common symptoms include:

• A mole that changes in size, shape or color
• Irregular borders or uneven color
• A spot larger than a pencil eraser
• A mole that continues to change over time
• Itching, bleeding or tenderness

A simple way to remember signs of melanoma is the ABCDE rule:

• Asymmetry
• Border irregularity
• Color variations
• Diameter larger than 1/4 inch (6 millimeters)
• Evolving appearance

Some dermatologists also recommend looking for the “ugly duckling sign,” meaning a mole or spot that looks noticeably different from the others on your body.

What Are the Main Risk Factors for Melanoma?

Anyone can develop melanoma, but certain factors increase your risk.

Risk factors for melanoma include:

• Skin frequently exposed to the sun or a history of blistering sunburns
• Using tanning beds
• Having fair skin or skin that burns easily
• Having many moles or atypical moles
• A family history of melanoma, particularly in a first-degree relative

How Important Is Early Detection?

When melanoma is in its early stages, it’s often easier to treat and less likely to spread. Regular skin checks can help identify suspicious changes before they become more serious.

• Check your skin once a month at home.
• Schedule annual skin exams with a dermatologist.
• Take photos of moles to monitor changes over time.

When Should You See a Doctor?

You should see a dermatologist if you notice a new spot on your skin or changes in an existing mole.

Talk to your dermatologist if you spot a mole that:

• Changes in size, shape or color
• Looks different from your other moles
• Bleeds, itches or becomes painful

To diagnose melanoma, your doctor may examine the area and perform a biopsy, which involves removing a small sample of tissue for testing.

Common Treatment Options

Treatment depends on the size, location and stage of the melanoma.

In the early stages, treatment often includes surgery to remove the melanoma and a small amount of surrounding skin. Your surgeon may also remove a nearby lymph node to see if the cancer has spread. This procedure is called a sentinel lymph node biopsy.

If it has spread, treatment may include:

• Surgery to remove affected lymph nodes
• Immunotherapy to help the immune system fight cancer cells
• Targeted therapy, radiation therapy or other advanced treatments

“While immunotherapy has revolutionized the care of melanoma, early detection gives people with melanoma the best chance for a cure,” says Jeffrey D. Wayne, MD, a physician who specializes in melanoma and sarcoma surgery at Northwestern Medicine.

Your care team will recommend treatment based on whether the melanoma has spread and which parts of the body are affected.

How Can You Lower Your Risk?

Although not all cases of melanoma can be prevented, there are several ways to reduce your risk and protect your skin.

• Limit time in direct sunlight and seek shade when possible, especially during peak hours between 10 am and 4 pm.
• Wear sunscreen with an SPF rating of 30 or greater, protective clothing and a wide-brimmed hat.
• Avoid tanning beds.
• Get regular skin checks and report suspicious changes to your doctor.

Protecting your skin from ultraviolet (UV) damage is one of the most effective ways to reduce your chance of developing melanoma.

Common Misconceptions About Melanoma

There are several myths about melanoma that can lead to delayed diagnosis.

Myth: Only older adults get melanoma.
Fact: Melanoma can affect people of all ages.

Myth: People with darker skin can’t develop skin cancer.
Fact: Anyone can develop melanoma, regardless of skin tone. In people with darker skin, melanoma is more likely to develop in the palms of the hands, soles of the feet or under the nails.

Myth: Only skin that is exposed to the sun is at risk.
Fact: Some forms of melanoma develop in areas that receive little or no sun exposure.

Myth: Melanoma is just a mole.
Fact: A changing mole can be an early warning sign of melanoma, but the disease can also appear as a new spot or growth on the skin.

Checking your skin once a month and paying attention to changing moles can help you spot melanoma early. If you notice any of the ABCDE warning signs, schedule an appointment with a dermatologist.